Garden Grove Unified School District Precalculus Q3 Benchmark Review 09‐10 Scientific Calculators are permitted 1. T 15.0 What are the polar coordinates of the point with rectangular coordinates (5, 6) ? (Round to tenths) 2. T 15.0 What are the rectangular coordinates 5p of the point with polar coordinates (6, ) ? 6 3. T 15.0 Which of the following polar coordinates does not describe (-2 2 ,-2 2) ? Explain why. 5p ) 4 p c) (-4, ) 4 a) (4, 3p ) 4 p d) (4,- ) 4 b) (4,- 4. T16.0 What is the polar equation for the circle with the equation x 2 + (y - 3) 2 = 9 ? 11. T18.0 What is the first step to find the three third roots of i? 12. T 18.0 What are the cube roots of 8(cos135∞ + i sin135∞) ? Leave answers in trigonometric (polar) form. 13. T 18.0 What are the 4th roots of -1? 14. T 18.0 What is (1 + i 3)8 ? Leave answer in trigonometric (polar) form. 15. T 18.0 Express (-1 + i)10 in standard form. 16. MA 1.0 Name three representations for point p: 5. T16.0 What is the polar form of the equation 3x - 4y = 12 ? 6. T 16.0 What is the polar equation for the circle with the rectangular equation x 2 + y 2 = 25 ? p π 0 7. T17.0 If z1 = 8(cos 45∞ + i sin 45∞) and z2 = 4(cos 30∞ + i sin 30∞) , a) what is z1 ∑ z2 ? b) what z is 1 ? z2 4p 4p 8. T17.0 What is 2(cos + i sin ) in a + bi 3 3 form? 17. MA 1.0 A ship is heading north at 15 knots. The current is moving northeast at 4 knots. Draw a vector that represents the resulting velocity of the ship. 9. T 17.0 What is the trigonometric (polar) form of ( 3 - i) ? 18. MA 1.0 What is the rectangular form of the equation 2 = r cos(q - 30∞) ? 10. T 17.0 What is the standard form (a + bi) of 3 5p 5p the complex number (cos + i sin ) ? 2 3 3 19. MA 1.0 Rewrite the following polar equation in rectangular form: r = 2csc q Precalculus Q3 Benchmark Review 09‐10 Garden Grove Unified School District Precalculus Q3 Benchmark Review 09‐10 Scientific Calculators are permitted 20. MA 1.0 Which of the following polar coordinates describes (- 3,1) ? A. (2, 150°) C. (-2, 150°) B. (2, 30°) D. (-2, 30°) 21. MA 1.0 What are the rectangular coordinates of the point with polar coordinates Ê 11p ˆ Á 3, ˜? Ë 6 ¯ 22. MA 2.0 How is -169 + -25 - -100 written in a + bi form? 23. MA 2.0 What is the square of 6(cos 45∞ + i sin 45∞) ? Leave in polar form. 28. LA 7.0 In the figure below, which of the following statements is true? a b c A. a + b = c B. c+ b = a C. a + c = b D. b = c - a 29. LA 7.0 In parallelogram ABCD, vector AD is 5,1 and vector AC is 10,5 . What is vector AB? B C A D 24. MA 2.0 Find the cube of 5(cos20∞ + i sin 20∞) and express in standard form. 30. LA 7.0 a vector has an initial point P(1, 2) and a terminal point T(4, 4). A) Find the component form of PT B) Find the magnitude of PT 5p 5p ˆ Ê 25. MA 2.0 What is 4 2 Á cos + i sin ˜ in Ë 4 4¯ a + bi form? 31. LA 12.0 What is the dot product of 3, 4,-2 and 1,-3,-5 ? 26. MA 2.0 What is the value of (-1 + i) 7 ? 27. LA 7.0 Vectors a andb are shown below. What is the sum of a and b ? a b a = 7, 3 b = 5,6 Precalculus Q3 Benchmark Review 09‐10 32. LA 12.0 Which pair of vectors is perpendicular? Explain why. A. 3,-2 and -2, 3 B. 3,-2 and 2,-3 C. 3,-2 and 2, 3 D. 3,-2 and -3,2 Garden Grove Unified School District Precalculus Q3 Benchmark Review 09‐10 Scientific Calculators are permitted 33. LA 12.0 Under what conditions is vector a, b perpendicular to vector 3,-1 ? A. 3,-1 ∑ b, a B. a, b ∑ 3,-1 C. 3,-1 ∑ a, b D. a, b ∑ -1, 3 =0 =0 = -1 = -1 34. LA 12.0 The dot product of two vectors produces: A) B) C) D) a vector A scalar the magnitude of the vector A direction angle Precalculus Q3 Benchmark Review 09‐10 Garden Grove Unified School District Precalculus Q3 Benchmark Review 09‐10 Scientific Calculators are permitted Answer Key 1. ( 61,50.2∞) 17. 2. (-3 3, 3) Resultant vector 3. d 15 4. r = 6sin q 5. r = 12 3cosq - 4 sin q 4 6. r = 5 7. a) 32(cos 75∞ + i sin 75∞) b) 2(cos15∞ + i sin15∞) 8. (-1,-i 3) 9. 2(cos 11p 11p + i sin ) 6 6 3 3 3 10. ( i) 4 4 11. È Ê p 2pk ˆ Ê p 2pk ˆ ˘ z = 3 1 ÍcosÁ + ˜ + i sin Á + ˜ when k = 0,1,2 Ë ¯ Ë6 6 3 3 ¯ ˙˚ Î 18. 4 = 3x + y 19. y = 2 20. A Ê 3 3 3ˆ 21. Á ,- ˜ 2¯ Ë 2 22. 8i 23. 36(cos90∞ + i sin 90∞) 125 125 3 24. ( + i) 2 2 12. 2(cos45∞ + i sin 45∞), 2(cos165∞ + i sin165∞), 2(cos285∞ + i sin285∞) 25. -4 – 4i 13. (cos 45°+ i sin 45°), (cos 135°+ i sin 135°), (cos 225°+ i sin 225°), (cos 315°+ i sin 315°) 26. -8 - 8i 14. 256(cos 120° + isin 120°) 15. -32i 16. Ex: (7, 5p 7p p ), (7,- ), (-7,- ) 6 6 6 Precalculus Q3 Benchmark Review 09‐10 27. 12,9 28. B 29. 5, 4 30. 31. 32. 33. 34. A) (3, 2) B) 1 C B B 13